Loans and Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 1,327,739	$ 1,163,644
Less allowance for loan losses	(15,579)	(14,855)
Total loans, net	$ 1,312,160	$ 1,148,789
Total gross loans, net of deferred fees, (Percentage)	100.00%	100.00%
Commercial [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 865,852	$ 761,457
Total gross loans, net of deferred fees, (Percentage)	65.20%	65.50%
Commercial [Member] \| Owner occupied RE [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 317,262	$ 285,938
Total gross loans, net of deferred fees, (Percentage)	23.90%	24.60%
Commercial [Member] \| Non-owner occupied RE [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 301,360	$ 239,574
Total gross loans, net of deferred fees, (Percentage)	22.70%	20.60%
Commercial [Member] \| Construction [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 32,332	$ 33,393
Total gross loans, net of deferred fees, (Percentage)	2.40%	2.90%
Commercial [Member] \| Business [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 214,898	$ 202,552
Total gross loans, net of deferred fees, (Percentage)	16.20%	17.40%
Consumer [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 461,887	$ 402,187
Total gross loans, net of deferred fees, (Percentage)	34.80%	34.50%
Consumer [Member] \| Real estate [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 250,483	$ 215,588
Total gross loans, net of deferred fees, (Percentage)	18.90%	18.50%
Consumer [Member] \| Home equity [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 150,371	$ 137,105
Total gross loans, net of deferred fees, (Percentage)	11.30%	11.80%
Consumer [Member] \| Construction [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 38,766	$ 31,922
Total gross loans, net of deferred fees, (Percentage)	2.90%	2.70%
Consumer [Member] \| Other [Member]
Composition of loan portfolio
Total gross loans, net of deferred fees	$ 22,267	$ 17,572
Total gross loans, net of deferred fees, (Percentage)	1.70%	1.50%

Loans and leases receivable net of deferred income percentage.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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